Abstract
Aims
Increased matrix metalloproteinases activity and reduced nitric oxide (NO) bioavailability contributes to development of hypertension and this may be associated with a defective l-arginine-NO pathway. Exogenous l-arginine improves endothelial function to prevent the onset of cardiovascular disease, but the mechanism by which this is accomplished remains unclear. We determined the effects of exogenous l-arginine infusion on vascular biomarkers in patients with hypertension.
Main methods
Venous blood samples were obtained from seven patients with hypertension (45 ± 5 yrs., HT group) and eleven normotensive men (37 ± 3 yrs., CT group) before and during a 30-min intravenous l-arginine or saline infusion. Nitrite concentration was evaluated by ozone-chemiluminescence method; metalloproteinase-2 (MMP-2) and metalloproteinase-9 (MMP-9) activities were detected by zymography; tissue inhibitor of metalloproteinases-1 (TIMP-1) and 8-isoprostane concentrations were measured by enzyme-linked immunosorbent assay (ELISA); and thiobarbituric acid reactive substances (TBARS) were determined by colorimetric assay.
Key findings
At baseline, nitrite, TIMP-1, and MMP-2 activity were similar between the groups (P > 0.05), but MMP-9, TBARS and 8-isoprostane were higher in HT group (P ≤ 0.03). During l-arginine infusion, nitrite increased only in control group (P = 0.01), while MMP-2, MMP-9 activities, MMP-9/TIMP-1 ratio and 8-isoprostane decreased in HT group (P ≤ 0.02). There were no significant changes in vascular biomarkers between groups during the saline infusion (P > 0.05).
Significance
Exogenous l-arginine diminished metalloproteinase-2 and -9 activities and MMP-9/TIMP-1 ratio along with restoring the oxidative stress balance in patients with hypertension
Originalsprog | Engelsk |
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Tidsskrift | Life Sciences |
Vol/bind | 157 |
Sider (fra-til) | 125-130 |
Antal sider | 6 |
ISSN | 0024-3205 |
DOI | |
Status | Udgivet - 15 jul. 2016 |